A Serf was eather a pesant or a slave. They worked on the mannor or a feif, for a noble or a vassle. The serfs wer hard workers so in return the nobles or the vassles would give them food and a little parcen of money. Some nobles or vassles would let their serfs stay on ther land in return. Later in the the vassles or nobles would let their serf buy their freedom (this was right afret the crusades). As that happend, everything grew weak.
